I am experiencing some weirdness with my LiFePO4 batteries. I use them stacked in a prodigy v3 from puresmoker for 6volts. So, I put them in the charger, and one charges (as indicated by a red light), and the other acts as though it is still chaged (as indicated by a green light). If I switch the batteries, the same battery still indicates being fully charged. This is not good, correct? But I don't know what it means, or what I need to do about it.